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PubMedDate not supplied

Comparison of methods to wash liquid-stored red blood cells and red blood cells frozen with high or low concentrations of glycerol.

The efficiency of washing liquid-stored red blood cells and red blood cells frozen with high or low glycerol concentrations was evaluated by measuring the recovery of red blood cells in vitro, supernatant hemoglobin, extracellular potassium and red blood cell potassium levels, supernatant osmolality, residual 125I albumin, glycerol, hypoxanthine, and di-2-ethylhexyl phthalate (DEHP) levels. Four commercial washing systems were studied, three which used sodium chloride solutions with serial or continuous-flow centrifugation and one which used sugar solutions and dilution/agglomeration. Washing was most efficient using sodium chloride solutions in the IBM Blood Processor, an automated serial centrifugation procedure and in the Fenwal Elutramatic, a continuous-flow centrifugation procedure. Less efficient washing was achieved in the Haemonetics Processor 15, a continuous-flow centrifugation procedure and the least efficient washing occurred using the original and modified dilution/agglomeration procedures. To achieve the most efficient washing, three principles must be utilized: concentration of the red blood cells to hematocrit values of 90 per cent, prior to washing or freezing. Liquid-stored red blood cells concentrated to hematocrit values of 90V per cent should be diluted with hypertonic sodium chloride solutions prior to recovery and washing. Red blood cells containing 20 per cent or 40 per cent W/V glycerol should be diluted with hypertonic sodium chloride solutions before recovery and washing. Finally, on-line dilution should be achieved in the washing systems that use continuous-flow centrifugation.

Blood Preservation↗

PubMedDate not supplied

The utility of platelet washing using an automated procedure for severe platelet allergic reactions.

Increased use of platelets in patients requiring chronic platelet support has increased platelet transfusion reactions. The authors reviewed more than 300 platelet transfusion reactions, evaluated an automated platelet washing technique, and studied the effectiveness of washing platelets to reduce reactions. Febrile reactions (66%) were most frequently reported, followed by moderate and severe allergic reactions (15%), and urticaria alone (19%). Washed platelets were prepared by an automated technique (IBM/COBE 2991). In vitro studies indicated no apparent adverse effects to the platelets due to the wash procedure, and in vivo studies demonstrated good platelet increments in 10 thrombocytopenic patients. Twenty-two patients with histories of platelet transfusion reactions received a total of 554 washed platelet transfusions. Washed platelets were not effective in reducing febrile transfusion reactions in 16 patients receiving 347 washed products. The efficacy of washed platelets in reducing transfusion reactions was demonstrated in six patients with histories of severe allergic reactions who received 207 washed products. Severe allergic reactions were completely alleviated in this group. In conclusion, automated platelet washing is simple and efficacious in preventing or reducing the severity of allergic reactions to platelet transfusions.

Adult↗

PubMedDate not supplied

Viability and functional integrity of washed platelets.

The viability and functional integrity of saline- and ACD-saline-washed platelets were compared with those of unwashed platelets. After template bleeding time (TBT) was measured, 15 healthy volunteers underwent plateletpheresis and ingested 600 mg of aspirin. Autologous 111In-labeled platelets were transfused: unwashed (n = 5), washed with 0.9 percent saline solution (SS) (n = 5), and washed with a buffered 12.6 percent solution of ACD-A in 0.9 percent saline solution (n = 5). After transfusion, we measured TBT at 1, 4, and 24 hours; platelet survival at 10 minutes and 1, 4, and 24 hours and daily for 6 days; and the percentage of uptake in liver and spleen by quantitative whole-body radionuclide scintigraphy at 24 and 190 hours. We found that saline washing affected platelet recovery, 23.47 +/- 12 percent (p less than 0.001) as compared to 52.43 +/- 17 percent (p less than 0.002) for ACD-saline and 73.17 +/- 8 percent for control; that saline washing resulted in a greater liver uptake than control and ACD-saline-washed platelets (31.9 +/- 8% [p less than 0.001] vs 17.7 +/- 4.1 and 19.3 +/- 2.1% [p greater than 0.1], respectively); that, unlike control and ACD-saline-washed platelets, saline-washed platelets did not shorten bleeding time; and that neither type of washing affected survival. Although ACD-saline washing affects recovery, it also results in intact function, normal survival, higher recovery than SS platelets, and no significant liver uptake.

Bleeding Time↗

PubMed1998

Comparative analysis of p53 mutations in bladder washings and histologic specimens.

Mutations in the tumor suppressor gene p53, analyzed in bladder washings, have positive predictive value for the progression of superficial bladder cancer to invasive disease. Bladder washings reflect the general status of the urothelium, and because sampling of bladder washings can be performed as an outpatient procedure, patients can be monitored more carefully. To determine the actual value of bladder washing specimens in assessing the p53 status of histologic specimens, we used the technique of polymerase chain reaction-single-strand conformation polymorphism to analyze bladder washings and the synchronous tumors of 15 patients for the presence of p53 mutations. A significant correlation (2-tailed Fisher's exact test) between the p53 status of bladder washings and histologic specimens was observed if the 2 were compared among the specimens of a single patient. Overall, in 2 patients the mutation present in the tumors was not detected in the bladder washings, and in 1 patient the mutation in the bladder washing was not detected in the histologic specimens. These conflicting results obtained with bladder washings and histologic specimens could be explained mainly by the architecture of the tumors. The observed specificity of 86% and sensitivity of 75% emphasizes that although the correlation between the 2 methods is good, in a number of cases they are complementary to each other. The analysis of p53 mutations in at least 2 bladder washings gives insight into the p53 status of the synchronous tumors.

Genes, p53↗

PubMed1997

Effects of Prolonged Washing on Primary and Secondary Transport Processes at the Plasma Membrane in Red Beet Storage Tissue.

Changing patterns of enzyme activity and solute transport in response to washing were investigated in red beet (Beta vulgaris L.) storage tissue. Washing had a pronounced effect on the plasma membrane (PM) H+-ATPase with an increase in both hydrolytic and proton-pumping activities. Immunoblotting indicated that this may be due, in part, to a higher amount of this enzyme in the PM of washed tissue. Activities of the tonoplast (V)H+-ATPase and pyrophosphatase fluctuated during a 4-d washing period, but overall showed no marked change in activity. In tissue discs sucrose (Suc), glucose (Glc), and fructose uptakes increased significantly in response to washing. Cycloheximide, cordycepin, and tunicamycin inhibited both Glc- and Suc-inducible uptake. Monensin also strongly inhibited inducible Glc uptake, but the effect on Suc was less marked. N-Ethylmaleimide inhibited both Suc and Glc uptake, with its effects being more pronounced in fresh tissue. Other protein-modifying reagents showed no significant difference in their level of inhibition between fresh and washed tissue. Transport studies, carried out using energized PM vesicles from fresh and washed tissue, indicated that there was no rise in Suc and Glc uptake rates in response to washing. Results with a range of inhibitors indicated that there was no marked change in transporter sensitivity in vesicles isolated from fresh and washed tissue. The results indicate that the well-described enhancement of solute transport in washed storage tissue may be due to an increased PM H+-ATPase activity rather than to changes in PM carrier activity or to changes in metabolism such as invertase activity.

Journal Article↗

PubMed2004

The in vitro quality of washed, prestorage leucocyte-depleted red blood cell concentrates.

BACKGROUND AND OBJECTIVES: No data are currently available on the quality of washed prestorage leucocyte-depleted red blood cell concentrates (RCCs). MATERIALS AND METHODS: Five groups of RCCs stored in additive solution (SAG-M) were washed. The groups differed in the age of RCCs (2-5 days or 11-15 days), the temperature during the washing procedure and a 6-h storage period (4 degrees C or room temperature) and the washing solution (saline, SAG-M or 5% albumin). We measured ATP, 2,3-diphosphoglycerate (2,3-DPG), haemolysis, blood cell count, Na(+), K(+), pH, pO(2), pCO(2) and lactate, before and after the washing procedure and hourly during the 6-h postwash storage period. RESULTS: The erythrocyte ATP content increased by 2-13%, relative to the baseline value, during the washing procedure. The 2,3-DPG level decreased by 15-35% in 2-6-day-old RCCs and by 30-40% in 11-15-day-old RCCs (relative to baseline values) during the washing procedure. In RCCs that were washed and stored at room temperature, and in 2-week-old RCCs, a further decrease in 2,3-DPG of up to 40%, relative to the baseline value, was observed during the 6-h postwash time-period. CONCLUSIONS: Washing of RCCs stored in SAG-M results in a considerable, significant loss of erythrocyte 2,3-DPG, especially in older RCCs. This loss increases in during a 6-h storage period postwash, even at 4 degrees C. This loss of erythrocyte quality might well outweigh the benefits of washed SAG-M RCCs during massive transfusion in neonates.

2,3-Diphosphoglycerate↗

PubMed1998

Washing machine usage in remote aboriginal communities.

The use of washing machines was investigated in two remote Aboriginal communities in the Anangu Pitjantjatjara homelands. The aim was to look both at machine reliability and to investigate the health aspect of washing clothes. A total of 39 machines were inspected for wear and component reliability every three months over a one-year period. Of these, 10 machines were monitored in detail for water consumption, hours of use and cycles of operation. The machines monitored were Speed Queen model EA2011 (7 kg washing load) commercial units. The field survey results suggested a high rate of operation of the machines with an average of around 1,100 washing cycles per year (range 150 and 2,300 cycles per year). The results were compared with available figures for the average Australian household. A literature survey, to ascertain the health outcomes relating to washing clothes and bedding, confirmed that washing machines are efficient at removal of bacteria from clothes and bedding but suggested that recontamination of clothing after washing often negated the prior removal. High temperature washing (> 60 degrees C) appeared to be advantageous from a health perspective. With regards to larger organisms, while dust mites and body lice transmission between people would probably be decreased by washing clothes, scabies appeared to be mainly transmitted by body contact and thus transmission would be only marginally decreased by the use of washing machines.

Bedding and Linens↗

PubMed2006

Washing platelets with new additive solutions: aspects on the in vitro quality after 48 hours of storage.

BACKGROUND: Rare clinical conditions cause the need for washed platelet (PLT) concentrates (PCs). Saline-washed PCs can only be stored shortly, however, owing to lack of substrates for PLT metabolism. New PLT additive solutions (PASs) contain such substrates and might be used alternatively. The in vitro quality of apheresis PCs washed with Composol-PS or modified PAS-III (PAS-IIIM) stored up to 48 hours after wash was compared. STUDY DESIGN AND METHODS: Twelve blood donors underwent two apheresis procedures (A and B) collecting 6.0 x 10(11) PLTs in 500 mL of plasma with a least 2 weeks in between. The PCs collected by Apheresis A were stored for 3 days and then split in two equal units before washing with Composol-PS or PAS-IIIM. The PCs collected by Apheresis B were split after collection. One unit was released for transfusion and 1 unit was stored unwashed up to Day 6 and used as reference unit. In vitro testing was performed before and after washing as well as 24 and 48 hours after wash. RESULTS: After 48 hours of postwash storage, the units washed with either PAS showed acceptable results for hypotonic shock response (HSR), P-selectin expression, and pH, whereas PLT aggregability was significantly impaired. Throughout the storage, unwashed units showed better in vitro quality. HSR and P-selectin expression were similar before and immediately after the washing procedure. CONCLUSION: Based on these in vitro results, 48-hour postwash storage of washed PCs with the two PASs seems to be feasible. In vivo recovery studies, however, must confirm this finding in the future.

Blood Platelets↗

PubMed1990

Value of washings and brushings at fibreoptic bronchoscopy in the diagnosis of lung cancer.

A retrospective study was performed to evaluate the diagnostic yield for lung cancer from histological biopsy specimens and from washings and brushings for cytological examination taken at fibreoptic bronchoscopy. The records of 680 bronchoscopies were analysed. Of 300 patients eventually diagnosed as having a malignant lesion, 188 had had biopsy, washing, and brushing. Of these, 125 had endoscopically visible tumour (group A) and 63 had no abnormal findings or abnormal findings that were not diagnostic of malignancy (group B). In group A biopsy specimens gave a positive result in 76% of cases, washings in 49.6%, and brushings in 52%; biopsy material gave the only positive result in 22.4% of cases, washings in 2.2%, and brushings in 4.8%. In group B biopsy specimens were positive in 36.5%, washings in 38.1%, and brushings in 28.6%; biopsy gave the only positive result in 11.1% of cases, washing in 9.5%, and brushing in 3.2%. Washing had a higher diagnostic yield than brushing in group B. Biopsy and cytological examination of either washings or brushings were found to give over 95% of all positive results in group A, but in group B the combination of biopsy and washing was more often successful (94.3%) than biopsy and brushing (82.8%). It is concluded that for the maximum diagnostic yield in the diagnosis of lung cancer biopsy should be combined with cytology using both washings and brushings.

Bronchoalveolar Lavage Fluid↗

PubMed2006

Regular use of a hand cream can attenuate skin dryness and roughness caused by frequent hand washing.

BACKGROUND: Aim of the study was to determine the effect of the regular use of a hand cream after washing hands on skin hydration and skin roughness. METHODS: Twenty-five subjects washed hands and forearms with a neutral soap four times per day, for 2 minutes each time, for a total of two weeks. One part of them used a hand cream after each hand wash, the others did not (cross over design after a wash out period of two weeks). Skin roughness and skin hydration were determined on the forearms on days 2, 7, 9 and 14. For skin roughness, twelve silicon imprint per subject and time point were taken from the stratum corneum and assessed with a 3D skin analyzer for depth of the skin relief. For skin hydration, five measurements per subject and time point were taken with a corneometer. RESULTS: Washing hands lead to a gradual increase of skin roughness from 100 (baseline) to a maximum of 108.5 after 9 days. Use of a hand cream after each hand wash entailed a decrease of skin roughness which the lowest means after 2 (94.5) and 14 days (94.8). Skin hydration was gradually decreased after washing hands from 79 (baseline) to 65.5 after 14 days. The hand wash, followed by use of a hand cream, still decreased skin hydration after 2 days (76.1). Over the next 12 days, however, skin hydration did not change significantly (75.6 after 14 days). CONCLUSION: Repetitive and frequent hand washing increases skin dryness and roughness. Use of a hand cream immediately after each hand wash can confine both skin dryness and skin roughness. Regular use of skin care preparations should therefore help to prevent both dry and rough skin among healthcare workers in clinical practice.

Cross-Over Studies↗

PubMed1999

[Effects of mouth wash on the removing beclomethasone dipropionate delivered by pressurized aerosol metered-dose inhaler in the mouth].

Effects of mouth wash (mouth rinsing and gargling) on the removal of drug residues in both mouth and pharynx after the use of pressurized aerosol metered-dose inhaler (MDI) were studied. The concentration of beclomethasone dipropionate (BM) in mouth wash after a splay of Becotide inhaler was measured by the method using HPLC. The total amount of the removed BM was measured by a sum of the concentrations of BM in 4 or 5 times of mouth washes in the following 4 kinds of methods. In method 1, mouth wash was done with 5 times of water change after a splay of MDI on wetted mouth. In method 2, mouth wash was done with 5 times of change water on dried mouth. In method 3, mouth wash was done with 4 times of change saliva on wetted mouth. In these methods, the actual inhalation of BM was not done. In method 4, mouth wash was done with 5 times of change water after a splay and a inhalation on wetted mouth. The mouth wash procedures removed totally 47.9%, 51.1%, 31.3%, and 33.3% of a splayed amount of BM in each method, respectively. It was required for the removal of 90% of the totally recovered BM to do one time of mouth wash in method 1, two times in method 2, three times in method 3, and two times in method 4, respectively. These data suggest that the mouth wash procedure is shown to have prophylactic benefit for candidiasis induced by steroid delivered by MDI.

Administration, Inhalation↗

PubMed2000

Validation of acid washes as critical control points in hazard analysis and critical control point systems.

A 2% lactic acid wash used in a large meat-processing facility was validated as an effective critical control point (CCP) in a hazard analysis and critical control point (HACCP) plan. We examined the microbial profiles of beef carcasses before the acid wash, beef carcasses immediately after the acid wash, beef carcasses 24 h after the acid wash, beef subprimal cuts from the acid-washed carcasses, and on ground beef made from acid-washed carcasses. Total mesophilic, psychrotrophic, coliforms, generic Escherichia coli, lactic acid bacteria, pseudomonads, and acid-tolerant microorganisms were enumerated on all samples. The presence of Salmonella spp. was also determined. Acid washing significantly reduced all counts except for pseudomonads that were present at very low numbers before acid washing. All other counts continued to stay significantly lower (P < 0.05) than those on pre-acid-washed carcasses throughout all processing steps. Total bacteria, coliforms, and generic E. coli enumerated on ground beef samples were more than 1 log cycle lower than those reported in the U.S. Department of Agriculture Baseline data. This study suggests that acid washes may be effective CCPs in HACCP plans and can significantly reduce the total number of microorganisms present on the carcass and during further processing.

Abattoirs↗

PubMed2002

Effect of acid adaptation on survival of Escherichia coli O157:H7 in meat decontamination washing fluids and potential effects of organic acid interventions on the microbial ecology of the meat plant environment.

The acid tolerance of Escherichia coli O157:H7 may be pH inducible. Correspondingly, organic acid meat decontamination washing fluids may enhance the establishment of acid-adapted E. coli O157:H7 strains in packing plants, especially in mixtures with water washings from meat that may be of sublethal pH. Acid-adapted and nonadapted cultures of a rifampin-resistant derivative of the acid-resistant E. coli O157:H7 strain ATCC 43895 were tested to evaluate their survival in meat-washing fluids over a wide pH range. The cultures were exposed (10(5) CFU/ml) to acidic (2% lactic acid. 2% acetic acid, or a mixture of the two with water washings at ratios of 1/1, 1/9, or 1/99 [vol/vol]) or nonacid (water) meat washings for up to 14 days at 4 or 10 degrees C storage. E. coli O157:H7 survived in water washings, but the low storage temperatures and predominant natural microbiota synergistically inhibited its growth. Compared with acid-adapted populations, nonadapted populations displayed greater potential for survival and a tendency to initiate growth in water meat washings at 10 degrees C. The pathogen survived in most of the acid washings throughout storage (14 days), sometimes with minimal population reductions. Overall. nonadapted populations declined faster than acid-adapted populations, while the declines increased as the acid concentration and temperature of storage increased and were more dramatic in lactate, compared to acetate, washings. Acid-containing washings were selective for growth of lactic acid bacteria and yeasts. indicating that organic acid treatments may alter the microbial ecology of meat plant environments and potentially that of the meat. These results should be considered when selecting decontamination technologies for meat.

Acetic Acid↗

PubMed1999

Eradication of MRSA from carriers by means of whole-body washing with an antiseptic in combination with mupirocin nasal ointment.

Patients who are infected or colonised by MRSA should be isolated. However, isolation is very costly in terms of time and work. In order to shorten the period of isolation, attempts are being made to eradicate this organism from patients by means of whole-body washing in addition to nasal mupirocin treatment. The effectiveness of such washes has not yet been adequately confirmed by studies. From September 1997 to August 1998, therefore, in a clinical trial of MRSA eradication, 28 patients were washed for a period of five days with a 1:1 diluted preparation based on octenidine dihydrochloride. At the same time, the nose was treated with mupirocin. Before washing was begun, on day 4 during washing and on days 1, 4 and 7 after washing was completed, smears were taken from each patient from the nose, pharynx, forehead hairline, groin, axilla and wounds, and in the case of women from the sub-mammary area. Elimination of the MRSA was achieved in 21 out of 28 cases; in four cases the washing was discontinued on account of skin redness, in three cases no elimination could be achieved during the control period. In order to ensure the success of eradication and to minimise skin reactions due to the washing, the wash procedure must be standardised, and decontamination controlled microbiologically. The study confirms that MRSA can be eradicated by means of washing with an antiseptic combined with mupirocin treatment.

Administration, Topical↗

PubMed1991

Faecal indicator bacteria on the hands and the effectiveness of hand-washing in Zimbabwe.

Two aspects of hand-washing were explored in this study. Mothers and children from 80 families in Zimbabwe were asked to wash their hands in the traditional manner in sterile water. Mothers were asked to answere a socio-economic questionnaire. By using the questionnaire and observations in conjunction with the microbiological data from hand-washing, factors were identified which contributed to high counts on the hands. These were: high relative humidity, living on a commercial farm, and having an infant in the family. Mothers and children 1-5 years of age had higher counts than children of 6-12 years. People recently involved in outdoor physical activities such as farming had higher counts than those involved in other activities. The traditional hand-washing method was also compared with two other hand-washing methods: hand-washing using soap and hand-washing using a container known as the mukombe. Hand-washing with soap was the most effective method closely followed by hand-washing using the mukombe. The least effective method was traditional hand-washing.

Adult↗

PubMed2004

Value of washed sputum gram stain smear and culture for management of lower respiratory tract infections in children.

To date, the technique of washed sputum examinations has not been widely used in the clinical management of lower respiratory tract infections in children. A total of 224 sputum samples from 125 pediatric patients with lower respiratory tract infections were collected for washed sputum Gram stain smears and cultures. The results with these methods were compared to find correlation rates. The value of washed sputum cultures was assessed by examining the clinical responses of the patients who received antibiotic therapies instituted on the basis of the sputum culture results. Isolation rates of Haemophilus influenzae, Streptococcus pneumoniae, Moraxella catarrhalis, and Staphylococcus aureus were 22.4%, 9.4%, 4.9%, and 0.4%, respectively. For the prediction of H. influenzae, S. pneumoniae, and M. catarrhalis, the sensitivities of the washed sputum Gram stain smears compared with the culture method were 86.0%, 81.0%, and 90.9%, respectively. The specificities of the washed sputum Gram stain smear technique were 94.8%, 97.5%, and 98.1%, respectively. Overall, the sensitivity and specificity of the washed sputum Gram stain smear method were 85.5% and 87.2%, respectively. S. aureus was isolated from only one specimen; and washed sputum Gram stain smear estimation was correlated with the culture result. On the basis of the washed sputum culture results, appropriate antibiotic therapies were instituted for 93.3% of the patients with acute lower respiratory tract infections. This study suggests that the techniques of washed sputum Gram stain smear and culture are valuable and should be encouraged in clinical practice for the management of lower respiratory tract infections in children.

Bacteriological Techniques↗

PubMed1989

Exposure of bovine embryos to trypsin during washing does not decrease embryonic survival.

The objective of this study was to assess whether the exposure of zona pellucida-intact bovine embryos to the proteolytic enzyme, trypsin, during embryo washing has a detrimental effect on their subsequent survival and development. Embryos were collected nonsurgically from superovulated cows (n = 19) 7.5 d after insemination. Grade 1 and Grade 2 embryos were washed 12 times in modified Dulbecco's phosphate buffered saline (PBS) containing 0.4% bovine serum albumin (BSA), or in a series of five washes in BSA-PBS (without Ca++ and Mg++), two in 0.25% trypsin in Hank's solution (without Ca++ and Mg++) and five in PBS-BSA medium. Within 30 min after washing, embryos were either transferred nonsurgically into recipient cows, 7 to 8 d post estrus, or cryopreserved and transferred later. Frozen-thawed embryos from five of the donors were cultured for 72 h in vitro and their development was evaluated. Pregnancy rates did not differ (P>0.1) between recipient cows receiving control-washed and trypsin-washed embryos transferred fresh (51.0 vs 56.3%). However, pregnancy rates were higher (P<0.05) for frozen-thawed embryos treated with trypsin before cryopreservation than for frozen-thawed, control-washed embryos (68.2 vs 38.5%). Survival and development of embryos in vitro after cryopreservation did not differ between embryos subjected to the control- and trypsin-wash procedures. These results suggest that exposure of bovine embryos to trypsin for 2 to 3 min during washing did not have a detrimental effect on embryonic development, but may have enhanced cryopreservation of the embryos.

Journal Article↗

PubMed2004

Viral titers in nasal lining fluid compared to viral titers in nasal washes during experimental rhinovirus infection.

BACKGROUND: The concentration of rhinovirus in nasal wash specimens from infected volunteers peaks at 48-72 h after inoculation. The volume of expelled nasal fluid peaks at the same time, raising the question of whether the viral concentration in nasal wash reflects viral replication in nasal cells or merely the production of an increased volume of nasal fluid during a cold. OBJECTIVES: To determine the amount of rhinovirus in nasal lining fluid during colds before the nasal fluid has been diluted in a nasal wash. STUDY DESIGN: Rhinovirus titers were determined in nasal wash specimens collected daily for five days from 14 subjects with type16 rhinovirus infection. The urea concentration in nasal lining fluid equals that in blood. By determining the urea concentration in a nasal wash and comparing it to the urea concentration in blood from the same subject, it was possible to determine the amount of dilution of the nasal lining fluid. The dilution factor (reciprocal of the dilution) was then used to calculate the viral concentration in undiluted nasal lining fluid. RESULTS: The dilution factor in 70 nasal washes varied from 5 to 64. The viral GMTs (+S.E.) in nasal washes were 1.79 (+0.3) TCID(50)/ml at 24 h, 3.11 (+0.15) at 48 h, and 2.61 (+0.3) at 72 h. The viral GMTs in nasal lining fluid, based on urea adjusted values, paralleled those in nasal washes but were approximately one log higher. Virus concentrations returned to near baseline values by day 5. CONCLUSIONS: The temporal pattern of rhinovirus shedding observed in nasal wash specimens, with a peak in virus concentration at 48-72 h after infection, is a true indication of virus production in nasal cells and not an artifact of the increased amount of nasal fluid produced during the early phase of a cold.

Common Cold↗